I've found that good wet weather protection for blued steel and walnut rifles is to remove the metalwork from the stock and coat it liberally with cabinetmakers wax or similar. Allow to dry and buff lightly. This puts a thin but hard wax layer between the metalwork and the air, keeping water off the metal and giving you time to finish your hunt before stripping down to clean and dry.
It isn't foolproof, permanent or even something for a week hunting in a wet environment, but for days in the rain, it is good.
In humid environments I learnt to coat the metalwork under the woodline with petroleum jelly. Can make a mess, but is impervious to hot and wet conditions.
Those Steyr Mannlichers are fine quality rifles, keep it well and you won't regret using it in the field.
